Bearings for rotary cylinders, drums and the like



F. KAMINSKY Jan. 7, 1958 BEARINGS FOR ROTARY QYLINDERS, DRUMS AND THELIKE Filed May 17, 1955 2 Sheets-Sheet l Inveman FR/TZ KAM/N KY GENTJan. 7, 1958 F. KAMINSKY 2,319,130

. BEARINGS F OR ROTARY CYLINDERS, DRUMS AND THE LIKE Filed May 17, 19552 Sheets-Sheet 2 FRI T Z KAMM/S/(y nited BEARINGS non ROTARY CYLINDERS,DRUMS AND THE LIKE Fritz Kaminsky, .Leverkusen Germany,- assignor-to:Fell

ner & Ziegler G. in. b. H.,. Frankfurt am Main, Germany APPIica'tiOn May17, 1955; Serial No; 509 081 Claiins priority,- applicatiomGermany Marchlz, 1955 Claiins. (Cl; 308 -234)" Thisinventionrelatestoiimprovements inrotary treatment cylinders," drums:and the like, inc1udingrotary,cy-.

lindrical or tubularfurnaces; drying drums, mixing,

drums; pre-h'eatingand cooling drums and so on. The

cylindrical bodies of these machines are. mounted 1 on.

support rollers'by means of raceringsyprovided on such bodies; Rotaryfurnaces are generally. arranged somewhat inclined relatively to thehorizontal, andthe position of arotary furnacewithjits :racerings ismaintained onthe"associated support rollers by means of additionalpressure-rollers which bear againstithe appropriate side face ofaracering.

Themechanical stresses to which the support rollers and the raceringsare subjected is .very considerable. In most'cases no materialis'hardand homogeneous enough to" be-capable of withstanding withoutstructural damage the high pressures "whichoccur 'in non-stop day andnight.

operation withapproximately line contact between the rollers andassociate surfaces. Thus scale peelings, grooving fractures anddeformations oftenoccur at the surfacesof the support'rollers'andat thesurfaces of the racerings;

According to the present day stateof the rotary. furs nace art,precautions have been takento allow the furnace drurn 'with theassociated racerings to be displaced longitudinally with respect to thesupportrollers. In fact it h'as it been conventional practice fordecades to position the support'rollers with their axlesslightlyinclined with" respect to the axis of the rotary furnace insteadof straight. If the racerings of the rotary furnace press against theinclinedsupportrollers under the influence of theconsiderabledeadweight' components dueto the drum casing, furnace lining andfuel, theinclinedfurnaceibody is subjected-to a kindof screwaction tending tomoveit slowly in'an upward direction. Dependingon the size of 1the-rotary furnace; a longitudinal distance of approximately 20-to-40mm. willbechosenbetween the rigidly mounted upper and lower pressurerollerswhich are "adapted to the furnace inclination;

roller surfaces wheneverthe furnace drum presses with its -raceringflank against theupper pressure roller in the course of the'movementwhich said drum is forced to perform by the helicalforce'; With reducedsurface friction; thefurnacedrum then slides slowly downwards. Whenitmoves subsequently into the bottom position determined by the bottompressure roller,a new upward movement is initiated when augmentedfrictional engagement occurs owing to the small quantities of oil' onthe roller surfaces drying out ordeteriorating.

Ifthe operators are careless, it can easily happen that the applicationofoil is overlooked. The dry support rollersiwould then cause'thefurnace drum to be moved bya helical force ofextremely great' forceagainst-the Aspersons skilled in the art will' upper pressure roller.know, there would then bea great danger ofbreakage ofthe rnounting=ofare upper pressure roller and also, of" thirftirnacelining bricks.Consequently, theoperating The operating personnelmust poura few dropsofoil ontothe support "atent Patented Jan. 7, 1958.

efiiciency of a *rotaryfurnace installation according te: the presentstate of the" art is. greatly dependentconthe:

reliability; of its attendants.

In order toobviate as much as possible the wear of-the": bearing.surfaces-between theracerings and the support rollers, it is also knownto try; to obtain a suspended con:

dition, i. e. to achieve a balance between thetende'ncy;

of the-rotary furnace body to slide downwards andthe ability of theinclined 'support rollers 'tovexerta helical;

forces Owing. to varying thermal expansion, in the longivv tudinalsense, of. the rotary-furnace body, a-slight shifting of-the rotaryfurnace body then occurs to a. certain: extent in the axial direction,which is desirable if strip. damage is to be prevented. But thesemeasures, which.

can.only betregarded-las measures of expediency, are

quite unsatisfactory. It is very easyfor bearings to be damaged-owingtOzthC inclined setting of the support rollers, and this .would have avery detrimental effect on the.:expensive. furnace lining and on theoperatingefficiency; of the-:whole installation.

Theobject of .the present invention is to obviate the.

aforesaid disadvantagesw The presentinvention is characterised in'thattwo pressurev rollers. are provided one at each side of a racering;

the lower ends of theaxles of these pressure rollers being mounted in across-member. to which a reciprocating movement. substantially parallelto the longitudinalaxis of .the .rotary cylindrical body, is imparted byautomaticallycontrolleddriving means. The latter may be mechani-.- cal,electrical hydraulic, or hydroelectric. By this means.

it is' ensured that the longitudinal movement of the rotary cylindricalbody in the two opposite directions is effected positively and thereforeuniformly at pre-determined. in n In fact,.the power means isdouble-act-- tervals of time. ing in thatit positively forces thecylindrical body up the inclination at which saidbody is set andthenapositively forces or controls said body downwards.

The cross-member carrying the pressure-rollers can be; mounted byanarrangement of parallel links on a baseplate, and the drive forproducing the reciprocating movea ment then acts either directly orthrough a leverageuponv thiscross-member. Lessfriction is -therebyproduced than would be the case with a slide guide arrangement.

for th-CIOSS-II11TllJEI-Whl0h is also possible. important since thegreat dead weight .of,,for example; a

This. is:

rotary furnace could result in considerable frictional.

forces. If it is a question of a particularly long rotary orso-called'tubular furnace, it is expedientto arrangea.

twin pressure roller system of this kind not only at one racering but attwo or more racerings, thereby-scone.

spondingly reducing the driving force required. for; 0137 the automaticoperation .of the drive of the aforesaid cross-member. With such a drivethe reciprocatingcrossmember may be arranged to actuate anelectzicswitchi. which, by way of a lifting magnet arrangement,controls] a valve, for examplea rotary valve, in such manner. as. toproduce the alternate to and fro movements of the. ram in the workingcylinderand thusthe to and. fromovements of the cross-member coupledthereto. In

this case it is of advantage to employ'a vertically work-1 ing cylinderhaving its lower end pivotally mounted on.

the base plate, its associate ram or pistonhavingthe up:

per end of' itsrod pivotally connected to the. armof the.

triangular lever.

The requisite driving energy for the to andfro displacement of the twinpressure roller arrangement can be considerably reduced if the mountingof the pressure roller operative against the dead weight of the rotaryfurnace or the like is associated with a counter-balance arrangement.For example, one of two links supporting this pressure roller on thebase plate may take the form of a lever presenting an arm for suspensionof the counter-weight. The-counter-weight itself can be varied,depending on the given circumstances, but it is also possible to shiftthe point of application of the counter-weight on the said lever arm.

This counterweight arrangement can be provided in association with thepressure roller of one racering, whilst the movable and positivelyreciprocated twin pressure roller arrangement is situated at a secondracering. Alternatively, this counterweight arrangement can beassociated with the movable and positively reciprocated twin pressureroller arrangement.

The bearing surfaces of the pressure rollers, and possibly also of thesupport rollers, are advantageously slightly rounded and althoughsuchrounded surfaces, when unloaded, make a point or line contact, onthe other hand when pressure is exerted a rounded surface whichoriginally was part circular will now be distorted so as to form part ofa shallow ellipse; T heresult is that no edge contacts can occur betweenthe rollers and the bearing surfaces of the racerings, a feature whichnot only contributes to further reducing the driving'power necessary,but which strain-hardens the surface structure both of the rollers andalso of the racerings and which, particularly with the use of grease oroil, conserves the said surfaces. Instead of scale peeling, grooving,fractures or deformations being brought about by particularly highpressures, as in the case of known rotary furnaces, thev means accordingto the invention produce a completely uniform and controllablelongitudinal movement in both directions of, for example, a rotary tubefurnace, and the rounded construction of the bearing surfaces of thepressure rollers also results in a roll polishing effect, as it were,which imparts a particularly long life to the parts despite thepositively effected reciprocatory movement. It is thus a decisiveadvantage, from the operational point of view, if the surfaces of allsupporting rollers as well as pressure rollers themselves are providedwith rounded surfaces.

In order to enable the invention to be readily understood, reference ismade to the accompanying drawings illustrating embodiments of theinvention, in which:

Figure 1 is a side view of a cylindrical rotary furnace with tworacerings, one in association with counterbalance means and the other inassociation with driving means for positively reciprocating the furnacelongitudinally.

Figure 2 is a view, partly in section and to a larger scale, of themeans associated with the racering on the right-hand in Fig. 1.

Figure 3 is a view, partly in section and to a larger scale, of thecounterbalance means associated with the racering on the left-hand inFig. l, and

Figure 4 is a diagram of an electrically controlled hydraulic drive forthe automatic and positive production of the reciprocating movement.

According to Fig. 1, the tubular body 1 of a rotary furnace is mountedin the usual manner ata slight inclinationof approximately 2 relativelyto the horizontal by means of its racerings 2 and 3 bearing upon supportrollers 4 and 5. The inclination of the cylindrical rotary furnace issuch that the racering 3 lies somewhat lower than the racering 2. Inorder to take up the pressure load component caused by the dead weightof the furnace body, a pressure roller 6 which bears against one sideface 7 of the racering 2 is mounted on a movable support. This support,as hereinafter explained, is carried upon two vertical parallel links,one of which is formed as a lever presenting an arm 8 on the end ofwhich a counter weight 9 is suspended.

Pressure rollers 12 and 13 bear against respective side faces 10 and 11of the racering The lower ends of the shafts of these pressure rollersare mounted in a guide member 14 and the latter is reciprocated bysuitable driving means as indicated by the double arrow in the Figure 1,the path of such reciprocationbeing substantially parallel to thelongitudinal axis 15 of the rotary furnace. The details of 'the' twinpressure roller arrangement on the one hand and the pressure rollerarrangement with counterweight compensation on the other hand will beexplained shape presenting a laterally extending arm formed at its outerend with an eye 23. A pivot pin inserted in the eye 23 is engaged by thedriving means so as to swing the triangular link element 18 about thepivot pin 20a to a certain extent, whereby the cross member 16 with thepressure rollers 12 and 13 carries out a reciprocating movementsubstantially parallel to the longitudinal axis of the furnace body.With this movement there also occurs a vertical displacement of thebearing surfaces of the pressure rollers 12 and 13 which are rounded asindicated by the reference numerals 24 and 25, relatively to the fiatside faces 10 and 11 of the racering 3.

The driving up and down of the pin having a bearing ,inthe eye 23 can beeffected, for example, mechanically 'by an eccentric or cam drive, leverdrive or the like. In

the present example, however, a hydraulic drive is provided, a ramcylinder 26 having itsv lower end pivotally mounted in'a bearing bracket28by means of, the pin 27.

The upwardly extending piston rod or ram 29 is pivotally connected atits upper end with the eye 23 of the triangular link 18. The referencenumeral 30 designates a pipe line for oil under pressure. draulicdriving apparatus, the reciprocation of the ram or piston in thecylinder 26 on the one hand causes the cylinder to pivot about the pin27 and on the other hand causes the triangular link 18 to pivot aboutthe bolt 20a.

The pistonv strokes in the cylinder 26 can be controlled by known means,many ditferent kinds of which are known with hydraulic drives. One suchcontrol is illustrated in Fig. 4. The cross-member 16 with its twopressure rollers 12 and 13 is reciprocated in the manner aforesaid andas indicated by the double arrow in Fig. 4.

In this diagram, however, the ram or piston rod 29 of the cylinder 26 isshown in a horizontal position acting directly upon the cross member 16at one end of the latter. At the other end, a rod 31 acts upon aswitching arrangement 32 which is adapted to switch on and off anauxiliary current for a relay-device 33 which acts upon a switch 34which opens and closes the main circuit. When the main circuit isclosed, a lifting magnet 35 is energised and operates a toothed rack 36.This toothed rack 36 meshes wtih a pinion 37 which is mounted on thespindle 38 of a rotary valve 39. The pressure fluid for the workingcylinder 26 with its associate piston 26a is delivered by a pump 40driven from an electric motor 41 which is likewise connected in the maincurrent line.

The actuation of the rotary valve 39 by way of the lifting magnet 35,being controlled by the switching oper- 1 ations initiated by the switch32, causes the pressure fluid to flow via the rotary valve 39 either byway of the pipe line 42 or the pipe line 43, to the one or the otherside of the piston 26a. The rotary valve 39 is connected to the pump 40by means of the pipe 44.

This electrical and hydraulic control arrangement is only indicated. ina purely schematic fashion in Fig. 4.

As is customary with hydraulic drives, a return pipe for Thus, with thishythe pressure fluid, a venting arrangement, a pressure relief valve andthe like would be provided in the piping system.

In Figure 3 the pressure roller 6 bears against a side face 7 of theracering 2, as in Figure 1. The pressure roller 6 is mounted in aguide-member 45 which is supported on a base plate 48 by verticalparallel links 46 and 47. The link pair 46 has connecting pivots 46a and46b, and the link pair 47 has pivots 47a and 47b. The links of the pair47 are fashioned as lever arms 49 mo tending laterally for a suitablelength. The outer end of each of these lever arms 49 is formed with aslot 50 into which is mounted a suspension pin 51 which can be adjustedalong the slots by means of a threaded rod 52 which comprises suitableeyes 53 engaging the pin 51. A rod 54 suspended from the pin 51 carriescounter weights 55, 55a, 5512. Therefore, by means of thesecounterweights 55, 55a and 55b acting by way of the lever arms of thelinks 47, the pressure roller 6 is additionally pressed against thebearing surface 7 of the meeting 2. The dimensions of the lever on theone hand and the value of the counterweights on the other hand are socalculated that this counter-pressure of the pressure roller 6 cansubstantially compensate the components of the load produced by thedeadweight of the furnace and constantly tending to move the latter in adownward direction. This pressure compensation can also be effected byarranging a plurality of such systems according to Fig. 3 at difierentracerings on the cylindrical rotary furnace.

The position of the lever 49 shown in Fig. 3 is that in which this leversettles when the furnace is in the hot operating condition, when thesaid furnace is in its highest position. When the furnace movement inone direction away from this highest position amounts to ap' proximately40 mm. and the furnace has moved from its highest position into thelowest position, the lever 49 then rises into the position shown inchain lines in Figure 3.

According to Fig. 3 the lever 49 is also provided with a hand-wheel 56and spindle 57. One purpose of this hand wheel-spindle arrangement is,when necessary, to swing the lever 49 relatively to the base plate 58 insuch a manner that the pressure roller 6 no longer bears against therunning surface 7 of the racering 2. Another purpose of this hand-wheeladjustment arrangement 56, 57 is to regulate exactly the appropriateapplication of the pressure roller 6 against the bearing surface 7 ofthe racering 2.

I claim:

1. Rotary treatment cylinder fitted with race-rings run ning on supportrollers for radial support and operatively engaged by cooperatingpressure rollers bearing laterally against said rings for the axialsupport of said rotary cylinder, wherein two pressure rollers areprovided one at each side of a racering each mounted for rotation on ashaft or the like, the lower end of said shafts of said pressure rollersbeing supported on a guide-member mounted for reciprocating movementsubstantially parallel to the longitudinal axis of said rotary cylinderand automatically controlled driving means operative to impartreciprocating movement to said guide member, whereby said rotarycylinder is positively forced and controlled in both axial directions.

2. Rotary treatment cylinder according to claim 1, wherein saidguide-member carrying said pressure rollers is supported on a base plateby a parallel link arrangement, and said driven means for producing thereciprocation of said cylinder is operatively connected to saidguidemember.

3. Rotary treatment cylinder according to claim 2, wherein one member ofthe parallel link arrangement is defined by a triangular lever pivotallymounted on said base plate and presenting a laterally extending armoperatively engaged by said driving means.

4. Rotary treatment cylinder according to claim 1, wherein saidguide-member carrying said pressure rollers is driven by hydraulic meansincluding a piston, and said guide member is fitted with means foractuating switch contacts for the electrical control of a distributorvalve controlling the alternate to and fro movement of said pistonoperative upon said guide-member.

5. Rotary treatment cylinder according to claim 4, wherein the lower endof the working cylinder for said piston is pivotally mounted on a baseplate, and said piston is pivotally connected at its upper end withmeans actuating said guide member.

6. Rotary treatment cylinder according to claim 1, wherein a pressureroller which takes the load resulting from the dead weight component ofsaid cylinder is mounted on a movable base provided with acounter-balance arrangement adapted for compensating said load.

7. Rotary treatment cylinder according to claim 6, wherein said movablebase is supported by a link presenting a lever arm adapted for thesuspension of a counterweight.

8. Rotary treatment cylinder according to claim 6, in which saidcounter-balance arrangement is provided at the pressure roller of oneracering while said cooperating pressure rollers are situated at asecond racering.

9. Rotary treatment cylinder according to claim 1, wherein the bearingsurfaces of said pressure rollers are rounded.

10. Rotary treatment cylinder in accordance with claim 9 wherein thebearing surfaces of said support rollers for said racering are rounded.

References Cited in the file of this patent UNITED STATES PATENTS

